A manufacturing method of a flexible electronic device may include the following steps. Firstly, a flexible substrate is formed on a carrier, such as glass substrate. Then, a component is formed on the flexible substrate. Then, the flexible substrate is peeled off from the carrier. In generally, the stiffness of the component is larger than that of the flexible substrate. As a result, during the flexible substrate being peeling off, the flexible substrate is easy to generate crack due to the stiffness of the component being larger than that of the flexible substrate.